A 28-year-old felon is going back to jail after police said he broke into an engineering firm, threatened employees, and nearly burned two offices down.It happened Tuesday night at the Cornerstone Structural Engineering Firm in Northwest Fresno.

It started with a break-in, after hours Fresno police said Michael Rankin barged into a building and threatened employees when they asked him to leave.

"The next thing they knew, he was inside an office, opening drawers, inside the kitchen and he had a knife, a letter opener type instrument, in his hand," said Lt Joe Gomez, Fresno Police Department.

Gomez said the employees left and called for help, but by the time officers showed up Rankin was barricaded inside the office on the second floor.

He was in there for hours. Gomez said, at one point, Rankin climbed out of a window, but went back inside. After that, Gomez said, he started breaking windows and lighting small fires.

"He started to light furniture on fire inside the office he was barricaded in, paper, cloth, he threw it out, and according to the report, some things caught fire, but officers put it out right away."

Officers had the building surrounded and there was nowhere to go but down for Rankin. Gomez said, the smoke ended up knocking him out and firefighters helped police get him out of the building.

"Rankin was down on the floor, suffering from smoke inhalation, so he was rushed to the hospital," said Gomez.

It turns out Rankin is a convicted felon and he was on probation for auto theft. On top of that, Gomez said, he had meth on him.

Still, at this point, officers are not sure why he decided to break into the engineering firm, and the owner of the business didn't want to talk about it.

Police said Rankin is ok but he is at the hospital on suicide watch.

As for the business, Action News was told there are two offices covered in soot and damaged by smoke.